Circle Definition: Lesson for Kids

Kids Activity for Becoming Familiar with the Formal Definition of a Circle:

Reminders and Facts:

• A circle is a round flat shape.
• The curved line that makes up a circle is called the edge of the circle.
• The center of a circle is the point that all of the points on the edge of the circle are the same distance from.

Materials Needed:

• Masking tape
• A large open space of floor
• A measuring tape
• Pencil and paper

Steps:

1. Use the masking tape to create a circle on the floor.
2. Have one student sit in the middle of the circle, and have the other students sit anywhere on the edge of the circle.
3. Use the measuring tape to measure the distance from the student in the center to each student on the edge of the circle and have each student on the edge of the circle write down the distance on a piece of paper.
4. Collect the pieces of paper and answer the activity questions.

Activity Questions:

1. What part of the circle does the student in the middle represent?
2. What part of the circle are the students, other than the one in the middle, sitting on?
3. What relationship do we find between the measurements that the students wrote down on each of their papers?

Activity Answers:

1. The student in the middle is at the center of the circle.
2. The students other than the student in the middle are sitting on the edge of the circle.
3. The measurements that the students took should all be very close to equal. This is because all of the points on the circle are the same distance from the center of the circle, and this demonstrates the definition of a circle as being a set of points that are all the same distance from a single point, which is the center of the circle.